Google panda update overview:
First let you know the first google panda update was introduced on feb 24th, 2011. Basically SEO factors are based on the pages of your site as well google panda updates are designed to target that are not great quality and truly spam. So this refers to the website having thin content whatever may be the number but in fact enough pages are flagged means your whole website is penalized. Obviously, focusing on site ranking when compared to original author’s content intends that a duplicate copy will definitely outrank and need to stop scrappers.
In the start site was called farmer update for a cause of low-quality, keyword stuffed articles have no real value or few visitors. Considering the above fact of panda update there is an indirect effect on article marketing, no matter how many back links you have attached and poor ranking. Articles and posts having keyword density approximately 2% get better results but not 3% or higher. Even if site has good repetition, competitive keywords still h2, h3 tags ranks lower.
Google penguin update overview:
When it seemed to google panda update, the google penguin update refers with SEO factors off your pages where as penguin concentrates on the site content you publish to build back links.
On April,24 the google penguin update was launched, here the google blog penguin is an important algorithm change targeted at web spam. The change directs to decrease in rankings for sites that are no good quality but violating quality guidelines of google. It is clear to typical black hat SEO tactics get a site in trouble when similar to keyword stuffing (web spam). A page content consisting of irrelevant outgoing links are easily perceived to the tactics having less potence cause penguin to flag your site. Its true to believe these sites are doing much more than white hat SEO.
Penguin deals with spam and keyword stuffing only relating to your site back links. Suppose you have submitted an article to thousands of article directories attached similar anchor links with your keywords get penalized by the penguin update. And also similar to the case the update focuses on link relevancy, if you have 100′s of back links inflow from completely unrelated niche markets effect ranking.